Electrochemical sensor based on Ti3C2 membrane doped with UIO-66-NH2 for dopamine

A Ti3C2 membrane was prepared by doping UIO-66-NH2 with Ti3C2 through hydrogen bonds. When the doping mass ratio of Ti3C2 and UIO-66-NH2 was 6:1, the electrochemical performance was optimal. Characterization was done by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical impedance spectroscopy (EIS) which exhibited hierarchical cave-like physiognomy, large specific area, outstanding electronic conductive network, and excellent film-forming property. Moreover, the Ti3C2 film was analyzed via atomic force microscopy (AFM), which displayed good mechanical properties and rough surface morphology. The fabricated Ti3C2 membrane/GCE sensor was applied to the detection of dopamine (working potential of + 0.264 V vs. Ag/AgCl) with LOD of 0.81 fM and a sensitivity of 14.72 µA fM-1 cm-2. It was demonstrated that the Ti3C2 membrane can be used to construct nonenzymatic sensors with excellent performance. The fabricated sensor has high selectivity and stability and has good practicability with recoveries of 101.2-103.5% and a relative standard deviation (RSD) of 1.2-2.4%.